Tech

Our optoacoustic sensor utilizes a novel ellipsoidal design in order to refocus the optoacoustic signal with minimal acoustic energy losses. The ellipsoid chamber achieves good acoustic properties for a wide range of environmental conditions. In contrast, most sensors rely on acoustic resonators for their signal amplification and require a well-controlled sample temperature.

To lower the system’s cost without compromising accuracy, a quartz tuning fork is used as a sound detector and a laser diode as a light source.

The prototype has been used for BC measurements in the lab and real-world conditions for the emissions monitoring of motorbikes, cars, and ships. It measures the mass concentration of BC particles in real-time (1 second resolution) and in transient conditions in excellent agreement with reference instruments. The sensor response is linearly dependent on the BC particle concentration, with a noise equivalent concentration (NEC) down to 1μg/m3.

In addition to detecting BC, our sensor can potentially monitor gas pollutants through the same principle. The same prototype has been used for CO2, NO2, and O2 measurements by utilizing a suitable wavelength light source. The sensor can have a significant economic impact on BC environmental measurements and source appointment technologies.

Read the interview of Leonidas >